HfC-TaC was employed to modify the C/SiC-ZrC composites and to improve their oxidation resistance. The composites were fabricated by the combined process of precursor infiltration and pyrolysis method and chemical vapor deposition method, and the oxidation resistance was evaluated by static oxidation tests (1600 °C/5 h and 1600 °C/20 h). According to the test results of flexural strength and mass loss, it is found that HfC-TaC can effectively improve the anti-oxidation behavior of C/SiC-ZrC composites without obviously decreasing their mechanical properties. By virtue of X-ray diffraction, scanning electron microscopy, and energy dispersive spectrometry, the crystal structure and microstructure of composites were analyzed. Results show that the superior anti-oxidation behavior of C/SiC-ZrC composites after HfC-TaC modification can be ascribed to the uniform element distribution and well-integrated components in the matrix.